Heating apparatus for liquid fuels



July 31, 1962 s. KOFINK 3,046,973

HEATING APPARATUS FOR LIQUID FUELS Filed Nov. 16, 1959 2 Sheets-Sheet 1 INVENTOR. S/EGFE/ED /(OF/NK ATTORNEYS July 31, 1962 s. KOFINK HEATING APPARATUS FOR LIQUID FUELS 2 Sheets-Sheet 2 Filed Nov. 16, 1959 INVENTOR. S/EGFP/E'D KoF/NK BY 7% WM gal/v ATTORNEYS United States Patent Office 3,046,973 Patented July 31, 1962 HEATING APPARATUS FOR LIQUID FUELS Siegfried Kofink, Esslingen am Neckar, Germany, assignor to J. Eberspacher, Esslingen am Neckar, Germany,

a German firm Filed Nov. 16, 1959, Ser. No. 853,389

Claims priority, application Germany Mar. 4, 1959 8 Claims. (Cl. 126-110) The present invention relates, generally, to liquid fuel heating systems and, in particular, to a fuel atomizer means.

In one type of conventional liquid fuel heating system, a combustion air blower is mounted in coaxial relation with the fuel combustion chamber and fuel atomizer means, fuel supply nozzle and a spark plug being disposed in the same radial plane relative to the axis of flow of the combustion air.

In such types of heating systems, the fuel injection nozzle and the hot plug are combined in a single antechamber located at the outer shell of the combustion chamber. The fuel, for example fuel oil, is introduced in such a manner that it drops onto the adjacent hot plug for atomization or conversion into gaseous state and ignition thereof. Other types of fuel atomizer arrangements known in the art convey the liquid fuel through the hollow shaft of the combustion air blower to an atomizer cup from which it is sprayed radially outwardly.

It is a primary object of the present invention to provide means achieving the result that the fuel particles which are atomized by centrifugal atomization means are immediately ignited in a uniform manner.

It is another object of the present invention to provide means conducive to a heating system wherein the fuel supply nozzle is so constructed and disposed in an antechamber at the wall of the combustion chamber that the supplied fuel impinges in the form of a continuous jet.

It is a further object of the present invention to construct the hub of the combustion air blower wheel as means for achieving centrifugal atomization of the injected fuel and to provide an igniting device in the radial plane of the spray zone thereof.

It is a further object of the present invention to provide means assuring the disposition of the fuel supply nozzle, which is recessed in the combustion chamber wall, so that it does not get too hot so the liquid fuel will not prematurely be converted into gaseous condition. The length of the antechamber and, therefore, the distance of the fuel supply nozzle from the combustion chamber, is dependent upon the particular operating temperatures Within the combustion chamber. In this connection, it is another object to provide a fuel supply device at the combustion chamber to assure that the fuel jet issuing therefrom is directed vertically downwardly.

The above and other objects of the invention will become further apparent from the following detailed description, reference being made to the accompanying drawing, showing a preferred embodiment of the invention.

In the drawing which illustrates the best mode presently contemplated for carrying out the invention:

FIG. 1 is a more or less schematic and diagrammatic representation of a heating apparatus pursuant to the present invention; and

FIG. 2 is a sectional view taken on line 22 of FIG. 1.

FIGURE 3 is a sectional view of the blower wheel structure.

Referring now to the drawing in detail, there is shown a heating apparatus pursuant to the present invention. Said apparatus comprises a housing 1 in which there is defined a pro-combustion chamber 1a for the heating device. An air blower motor 2 is mounted within the housing and is provided with .a shaft 11 to which there is keyed a blower wheel 3. The primary air drawn in by the blower is introduced axially into the combustion chamber through a blast conduction ring 4 as indicated by the arrow 12. The blower wheel 3 is provided with an elongated cylindrical hub 3a which extends toward the combustion chamber 10 defined in the housing 1. A fuel inlet means, here shown as a fuel injection nozzle 5, is mounted at the upper part of the combustion chamber 10 and in the upper part of the housing 1. More specifically, the nozzle 5 is disposed in a zone adjacent the front end of the hub 3a, the fuel nozzle being disposed within an antechamber 1b formed integral with or as a separate portion connected to one endof an inner tubular member or secondary combustion chamber member 1d located Within the housing 1. As here shown, the antechamber 1b extends substantially perpendicular to the axis of the wheel hub 3a and a hot or spark plug 6 is mounted in the housing 1 directly opposite to the antechamber lb or the fuel .injector nozzle disposed therein.

Fuel is supplied to the nozzle 5 through a fuel inlet line 13 as shown by arrow 14 and issues from the nozzle 5 in the form of an atomized jet 15 portions of which completely vaporize and mix with the combustion air and portions of which impinge on the forward part of the hub 3a.

The portions of the fuel jet which impinge on the hub 3a are further separated or divided when the liquid fuel particles strike the hub, the particles being partly evaporated and partly deflected toward the spark plugs 6 and atomized further by the rotating hub. As a result, a substantially dense cloud or veil of fuel is formed in the spray zone of the rotary hub 3a. This dense fuel cloud of atomized fuel particles results in the promotion of a rapid and complete ignition of the fuel, which is free of residue, when the heating apparatus 10 is operative. The fuel ignition proceeds radially along the secondary combustion chamber 1d.

The forward end of hub 3a may be provided in a conventional manner with blades or similar means to promote fuel atomization. In the present embodiment, the hub 25:: is provided with two disks or flanges 3b and 30 which are mounted on the periphery thereof. The disks prevent the combustion air which issues from the nozzle 16 defined by hub 3a, and the blast conduction ring 4 from entraining the fuel upon impingement thereof on the hub 3a.

The fuel-air mixture which is ignited in the precombustion chamber 1a is introduced into the secondary combustion chamber 1d as indicated by the arrows 17. The ignited fuel-air mixture passes through the flame ring 7 and enters the outer ring zone 1 over the bridge piece 1e.

In the secondary combustion chamber, there takes place the heat transfer into the primary air conveyed from blower 2w over the heat exchange surfaces of the combustion chamber 1c and the walls of the annular heat exchanger drum 1f.

Various changes and modifications may be made without departing from the spirit and scope of the present invention, and it is intended that such obvious changes and modifications be embraced by the annexed claims.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

l. A combustion device comprising an elongated tubular member having an opening at one end, baflie means therein defining within said tubular member a secondary combustion chamber and a pre-combustion chamber, a r0- 0 tary drum disposed coaxially in said pre-combustion chamber, a fan in said tubular member, means to rotate said drum and said fan to cause air to circulate in through one opening, around said drum, through said pre-combustion chamber to said secondary combustion chamber, means defining an ante-chamber leading radially inwardly into said pre-combustion chamber, nozzle means disposed in said ante-chamber arranged to produce a spray of fuel particles with portions thereof directed to impinge on said rotating drum whereby these portions are whirled by said drum into said combustion air stream to vaporize said particles, and means to ignite said air and fuel mixture in said pre-combustion chamber.

2. A combustion device according to claim 1, wherein said igniter means is disposed substantially on the'opposite side of said atomizer member from said ante-chamber.

3. A combustion device according to claim 1, wherein said drum has projections defined thereon.

4. A combustion device according to claim 3, wherein said atomizer member projections include spaced flanges secured to the periphery of said drum.

5. A combustion device according to claim 1, including an outer tubular housing surrounding said tubular member and having an opening at each end, said means defining an ante-chamber projecting from said tubular member in said outer housing, and blower means to direct air through said outer housing.

6. A combustion device according to claim 1, wherein said tubular member is closed at one end, and means for directing combustion gases around said secondary combustion chamber and laterally outwardly.

7. A combustion device according to claim 1, including an annular member surrounding said drum and defining a nozzle for the fiow of air therebetween and leading into said pre-combustion chamber.

8. A combustion device according to claim 1, wherein said fan and said drum are disposed in said tubular member adjacent the open end thereof, said means to rotate said drum and said fan including a motor having a shaft connected to said fan and said drum and arranged to close the center of the opening of said tubular member.

References Cited in the file of this patent UNITED STATES PATENTS 792,667 Rogers June 20, 1905 1,296,822 Legg May 11, 1919 1,357,276 Day Nov. 2, 1920 2,395,418 McCollum Feb. 26, 1946 2,757,662 Baier et a1 Aug. 7, 1956 2,777,508 Jurisich Jan. 15, 1957 

